1. Field of the Invention
The invention herein pertains to trimmer heads as are fitted on conventional electric and gasoline powered vegetation trimmers and particularly pertains to trimmer heads which can be easily attached and removed from various trimmer makes and models that accommodate either rigid cutting blades or flexible line. A rigid stainless steel blade is also described.
2. Description of the Prior Art and Objectives of the Invention
Many vegetation trimmer heads have been devised in the past for both rigid, rotatable plastic blades and for flexible nylon line. Certain prior art trimmer heads are formed from plastic and are molded in one piece. Other conventional trimmer heads are formed in two halves and are bolted or otherwise joined with pivotable, rigid blades supported between the halves. Such standard trimmer heads are releasably connected to the drive shaft of conventional vegetation trimmers as are used by homeowners, maintenance personnel and others for grass and weed cutting. As standard rigid plastic blades often break during use, the need for a trimmer head accommodating easy blade replacement has arisen. Likewise, the need for an inexpensive trimmer head which is both durable and easy to attach to different types of drive shafts has grown in recent years, as more and more manufacturers of vegetation trimmers market their products. Also, standard rigid blades break or chip when thick, heavy weeds and underbrush are encountered.
Conventional flexible line-type trimmer heads often use reels to provide a single "end" whereby the line is fed through the head as needed. Other line-type trimmer heads utilize one or more lengths of flexible line to provide a plurality of ends for trimming.
Currently available trimmer heads have certain disadvantages in that some are molded from relatively thin plastics which readily crack or break. Other trimmer heads may fit only one type of drive shaft, requiring distributors to stock individual trimmer heads for each type and model of trimmer. Some trimmer heads which are readily available are difficult to assemble and attach to a selected drive shaft by unskilled persons. Standard flexible line-type trimmer heads often do not provide the versatility required, and cannot be modified to support different numbers of available ends for trimming.
Thus, based on the problems and disadvantages of prior art trimmer heads, the present invention was conceived and one of its objectives is to provide a trimmer head having a spool-like shape which is integrally molded from conventional plastic.
It is yet another objective of the present invention to provide a low cost trimmer head which will maintain a plurality of rotatable rigid plastic or metal blades.
It is still a further objective of the present invention to provide a trimmer head which can be attached to different types of trimmer drive shafts in a convenient, secure and easy manner.
It is also an objective of the present invention to produce a trimmer head having a central channel for reception of a trimmer drive shaft, the central channel including a conical portion, a cylindrical portion and a polygonal portion.
An additional objective of the present invention features a flexible line-type trimmer head which will allow the user to select a variety of line ends, depending on the density and type of vegetation to be trimmed.
Still another objective of the present invention is to present a rigid stainless steel blade for use on heavy vegetation.
Yet another objective is to present a trimmer head which reduces the likelihood of breaking the trimming lines in the housing during use.
Various other objectives and advantages of the present invention will become apparent to those skilled in the art as a more detailed description is set forth below.